It is known that two or more vehicles moving along a roadway can cooperate as a road train or a “platoon” for mutually providing to the vehicles within the platoon various safety and efficiency benefits. A typical vehicle platoon includes a leader vehicle and one or more follower vehicles arranged serially along a single roadway lane. Larger platoons can involve many follower vehicles for providing enhanced efficiency, but ensuring the safety of to both the platooned vehicles as well as of the other non-platooning vehicles on the roadway most usually dictate the short single lane platoon incarnation.
The aerodynamic geometry of the vehicles within a platoon is a significant factor used in determining an ordering of the vehicles. As a general rule, a physically smaller vehicle following a physically larger vehicle will provide a greater benefit. Since commercial box trucks and tractors towing box trailers are in general taller and wider than most flatbed tractor trailer combinations, a maximum aerodynamic benefit and resultant fuel savings is realized by ordering vehicles classified this way such that the commercial box truck and tractors towing box trailers take the leader position(s) in the platoon, while the flatbed tractor trailer rigs take the follower position(s) in the platoon.
In addition to the above, maintaining a small distance or spacing between platooned vehicles gives greater benefit in terms of reduced energy consumption. However, holding a tight distance or spacing between platooned vehicles requires that careful attention be paid to various functional or environmental and operational characteristics and capabilities of the vehicles and other external conditions including the overall size of the platoon, weather conditions, relative braking abilities between vehicle pairs, relative acceleration abilities, relative load or cargo size and weight including required stopping distance, and the like. Special attention must also be paid to characteristics of the roadway such as roadway incline, decline, and turn radii. These various parameters implicate directly or indirectly the inter-vehicle safety considerations as well as the overall safety of multiple vehicle platoons.
In the single lane platoon incarnation described above, the vehicles participating in a platoon typically mutually cooperate to maintain a relatively fixed and constant (even or the same) distance between adjacent vehicles by exchanging deceleration commands, acceleration commands, and other command and data signals between adjacent vehicles of the platoon. On flat roadways, the even distance maintained between the vehicles is often fixed and constant in accordance with control protocols using combinations of global positioning systems (GPS) data sharing, deceleration command signal exchanges, and safety and efficiency algorithms. On graded roadways, the relatively even distance maintained between the vehicles is often modified to improve or otherwise maintain or enhance the overall safety and efficiency of the platoon. For example, the even distance maintained between the vehicles can be decreased during conditions of the platoon traversing an incline wherein the tendency of the overall platoon is to decrease speed slightly. Conversely, the even distance maintained between the vehicle can be increased during conditions of the platoon traversing a decline wherein the tendency of the overall platoon is to increase speed slightly. In any case, the relative distance between the vehicles of the platoon preferably remains substantially even, constant or the same in accordance with platoon control mechanisms and protocols in place.
For maintaining the preferred relatively fixed and constant (even or the same) distance between adjacent vehicles, many commercial vehicles that participate in platoons are highly sophisticated and are also equipped with adaptive cruise control (ACC) systems used for maintaining a safe relative distance between a host vehicle and a forward vehicle, and collision mitigation (CM) systems for avoiding or lessening the severity of impacts between a host and a forward vehicle using various combinations of transmission, vehicle retarder, and foundation brake controls.
In addition to the above, vehicles participating in a platoon typically share their positions with other vehicles of the platoon by communicating their GPS coordinate data with other vehicles using vehicle-to-vehicle (V2V) communications (“V2V Unicast” communications), and/or vehicle-2-vehicles (V2×) communications (“V2V Multicast” communications), and/or any other suitable communications that might be available. One SAE standard is J2945 directed in general to Dedicated Short Range Communication (DSRC), and a work in process portion of that standard is J2945/6 is directed to performance requirements for cooperative adaptive cruise control and platooning. J2945/6 is intended to define the data exchange that will be necessary for coordinated platoon maneuvers, and that definition of the categories should start with differentiating between platooning and ACC, then determining message sets and performance to realize cooperative vehicles.
Currently, the technique for vehicles participating in a platoon to share their position with other vehicles of the platoon involves determining, by each vehicle, its own GPS coordinate data, broadcasting by each vehicle its own GPS coordinate data to all of the other vehicles of the platoon using over-the-air communications (such as the J2945/6 communications), and receiving the GPS position data from all of the other vehicles of the platoon. In this way, each vehicle of the platoon knows the position(s) of each other vehicle of the platoon. The GPS coordinate data is then used by each vehicle to, among other things, establish the relatively even distance coordinated between the vehicles as generally described above.
Platoons that operate on public roadways, however, sometimes encounter conditions that enable more complicated platooning formations. For example, many roadways have more than one (1) lane, and some roadways have six (6) of more lanes. It would be useful to exploit available lanes when the traffic of other non-platooning vehicles may permit.
The present embodiments provide for a new and improved platoon management control system and method for rearranging three or more vehicles cooperatively travelling seriatim as a platoon along an associated roadway into a platoon arrangement other than the linear or single file formation.
The present embodiments further provide for a new and improved multi roadway lane platoon management control system and method for controlling the three of more vehicles cooperatively travelling as a multi-lane platoon along an associated multi-lane roadway into a platoon arrangement other than the linear or single file formation.
In addition, the present embodiments further provide for new and improved larger platoon sizes thereby enabling more vehicles to participate in the larger multi-lane platoon.